数字温度计

xiaosorry

已于 2023-11-26 18:37:39 修改

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CC 4.0 BY-SA版权

文章标签： fpga开发

于 2023-11-25 20:49:54 首次发布

本文链接：https://blog.youkuaiyun.com/xiaosorry/article/details/134618885

本文介绍了如何使用STM32F103C8T6的RTC功能获取日期时间，并通过SPI或I2C连接OLED屏幕实时显示，同时集成AHT20传感器测量温度和湿度。详细讲解了配置步骤、代码实现和实验效果。

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实验任务：

阅读资料了解 STM32F103的RTC（实时时钟）原理，使用带SPI或IIC接口的OLED屏显模块实现以下功能：

1) 读取STM32F103C8T6 内部的时钟(年月日时分秒)，日历(星期x），1秒周期，通过串口输出到PC上位机，；

2) 读取AHT20的温度和湿度，通过OLED，把年月份时分秒、日历和实时温度、湿度显示出来，2秒周期。

一、RTC时钟介绍

1.简介

RTC（Real Time Clock，实时时钟）是指安装在电子设备或实现其功能的IC（集成电路）上的时钟，通常是一个独立的定时器，即使电子设备处于关机状态也能继续运行。RTC使用一个精确的定时器和电池供电来保持时间的准确性。它通常提供了一个接口，使操作系统和其他软件可以读取和设置当前的日期和时间。RTC的原理涉及晶体振荡器、计数器、电源备份、控制逻辑和接口等主要方面。

STM32的RTC时钟是一个独立的定时器，具有连续计数的功能，在相应的软件配置下，可以提供时钟日历的功能。它包含用于管理低功耗模式的自动唤醒单元，在断电情况下仍可以独立运行，只要芯片的备用电源一直供电，RTC上的时间会一直走。此外，它还提供了两个32位寄存器，包含二进码十进数格式（BCD）的秒、分钟、小时（12或24小时制）、星期几、日期、月份和年份，以及一个具有中断功能的周期性可编程唤醒标志。系统可以自动将月份的天数补偿为28、29（闰年）、30和31天，还可以进行夏令时补偿。

2.原理

RTC内核完全独立于APB1接口，软件通过APB1接口对RTC相关寄存器访问。但是相关寄存器只在RTC APB1时钟进行重新同步的RTC时钟的上升沿被更新。所以软件必须先等待寄存器同步标志位（RTC_CRL的RSF位）被硬件置1才读。

RTC的预分频模块是一个20位的可编程分频器，它可产生最长为1秒的RTC时间基准TR_CLK。在RTC_CR寄存器中设置了相应的允许位后，每个TR_CLK周期中RTC会产生一个中断（秒中断）。该预分频模块在系统复位后自动装载，可从外部预装载寄存器读取其值。

RTC_CNT是实时时钟（RTC）的计数器寄存器。它用于存储RTC的计数值，该计数值与实时时间相对应。通过读取RTC_CNT寄存器，可以获取当前的实时时间。

二、STM32CubeMX配置生成

1.配置RCC

选择High Speed Clock(HSE)为Crystal/Ceramic Resonator

选择Low Speed Clock(HSE)为Crystal/Ceramic Resonator

2.配置SYS

在Debug中选择Serial Wire

3.配置I2C1

4.配置RTC

激活时钟和日历，初始化时间

5.配置USART

配置Mode为Asynchronous

6.配置SPI

7.配置GPIO

配置RES、DC、CS引脚

8.配置时钟

9.生成项目文件

三、代码编写

1.使用AHT20程序模板函数

修改函数使得温度读取函数在OLED上显示

void AHT20_Read_CTdata(uint32_t *ct) //??CRC??,????AHT20????????
{
		volatile uint8_t  Byte_1th=0;
	volatile uint8_t  Byte_2th=0;
	volatile uint8_t  Byte_3th=0;
	volatile uint8_t  Byte_4th=0;
	volatile uint8_t  Byte_5th=0;
	volatile uint8_t  Byte_6th=0;
	 uint32_t RetuData = 0;
	uint16_t cnt = 0;
	AHT20_SendAC();//?AHT10??AC??
	Delay_1ms(80);//??80ms??	
    cnt = 0;
	while(((AHT20_Read_Status()&0x80)==0x80))//????bit[7]?0,???????,??1,?????
	{
		SensorDelay_us(1508);
		if(cnt++>=100)
		{
		 break;
		 }
	}
	I2C_Start();
	AHT20_WR_Byte(0x71);
	Receive_ACK();
	Byte_1th = AHT20_RD_Byte();//???,??????0x98,??????,bit[7]?1;???0x1C,??0x0C,??0x08???????,bit[7]?0
	Send_ACK();
	Byte_2th = AHT20_RD_Byte();//??
	Send_ACK();
	Byte_3th = AHT20_RD_Byte();//??
	Send_ACK();
	Byte_4th = AHT20_RD_Byte();//??/??
	Send_ACK();
	Byte_5th = AHT20_RD_Byte();//??
	Send_ACK();
	Byte_6th = AHT20_RD_Byte();//??
	Send_NOT_ACK();
	Stop_I2C();

	RetuData = (RetuData|Byte_2th)<<8;
	RetuData = (RetuData|Byte_3th)<<8;
	RetuData = (RetuData|Byte_4th);
	RetuData =RetuData >>4;
	ct[0] = RetuData;//??
	RetuData = 0;
	RetuData = (RetuData|Byte_4th)<<8;
	RetuData = (RetuData|Byte_5th)<<8;
	RetuData = (RetuData|Byte_6th);
	RetuData = RetuData&0xfffff;
	ct[1] =RetuData; //??

}

2.主函数

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "rtc.h"
#include "spi.h"
#include "usart.h"
#include "gpio.h"
#include "stdio.h"
#include "oled.h"
#include "gui.h"
#include "i2c.h"
#include "dma.h"
#include "AHT20-21_DEMO_V1_3.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
int fputc(int ch,FILE *f){
 uint8_t temp[1]={ch};
 HAL_UART_Transmit(&huart1,temp,1,2);
 return ch;
}

void Show_Time(uint16_t Year,uint16_t Month,uint8_t Day,uint8_t Hour,uint8_t Minute,uint8_t Second)
{
	 GUI_ShowCHinese(0,0,16,"日期：",1);
   GUI_ShowNum(48,0,Year,4,16,1);
	 GUI_ShowString(80,0,(uint8_t *)"/",16,1);
	 GUI_ShowNum(88,0,Month,2,16,1);
	 GUI_ShowString(104,0,(uint8_t *)"/",16,1);
	 GUI_ShowNum(112,0,Day,2,16,1);
	 GUI_ShowCHinese(0,16,16,"时间：",1);
	 GUI_ShowNum(48,16,Hour,2,16,1);
  GUI_ShowString(64,16,(uint8_t *)":",16,1);
	 GUI_ShowNum(72,16,Minute,2,16,1);
	  GUI_ShowString(88,16,(uint8_t *)":",16,1);
	 GUI_ShowNum(96,16,Second,2,16,1);
}
void Show_Data(uint8_t  c,uint8_t t)
{
	GUI_ShowCHinese(0,48,16,"湿度",1);
	GUI_ShowString(32,48,(uint8_t *)":",16,1);
	GUI_ShowNum(60,48,c,2,16,1);
	GUI_ShowString(84,48,(uint8_t *)"%",16,1);
  GUI_ShowCHinese(0,32,16,"温度",1);
  GUI_ShowString(32,32,(uint8_t *)":",16,1);
	GUI_ShowNum(60,32,t,2,16,1);
	GUI_ShowCHinese(80,32,16,"℃",1);
	
}

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
  uint8_t Month,Day,Hour,Minute,Second;
	uint16_t Year;
	volatile int  c1,t1;
	uint32_t CT_data[2]={0,0};
	
  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_RTC_Init();
  MX_USART1_UART_Init();
  MX_SPI1_Init();
	MX_I2C1_Init();
	 MX_DMA_Init();
  MX_I2C1_Init();
	AHT20_Init();
  if((AHT20_Read_Status()&0x18)!=0x18) //?????,????????
	{
		AHT20_Start_Init();   //??????????
		Delay_1ms(10);
	}

  /* USER CODE BEGIN 2 */
  RTC_DateTypeDef GetData;  //???????
  RTC_TimeTypeDef GetTime;   //???????
  OLED_Init();
	OLED_Clear(0);
	
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
		AHT20_Read_CTdata(CT_data);   
	  c1 = CT_data[0]*100/1024/1024;  
	  t1 = CT_data[1]*200/1024/1024-50;	
    HAL_RTC_GetTime(&hrtc, &GetTime, RTC_FORMAT_BIN);
    HAL_RTC_GetDate(&hrtc, &GetData, RTC_FORMAT_BIN);
    Year=GetData.Year+2000;
		Month=GetData.Month;
		Day=GetData.Date;
		Hour=GetTime.Hours;
		Minute=GetTime.Minutes;
		Second=GetTime.Seconds;
		printf("日期：%d/%d/%d\r\n",Year,Month,Day); //串口打印日期
		printf("时间：%d:%d:%d\r\n",Hour,Minute,Second); //串口打印时间
		if(GetData.WeekDay==1){
			printf("星期一\r\n");
		}else if(GetData.WeekDay==2){
			printf("星期二\r\n");
		}else if(GetData.WeekDay==3){
			printf("星期三\r\n");
		}else if(GetData.WeekDay==4){
			printf("星期四\r\n");
		}else if(GetData.WeekDay==5){
			printf("星期五\r\n");
		}else if(GetData.WeekDay==6){
			printf("星期六\r\n");
		}else if(GetData.WeekDay==7){
			printf("星期天\r\n");
		}
	  printf("\r\n"); //串口打印时间
    Show_Time(Year,Month,Day,Hour,Minute,Second); 
		Show_Data(c1,t1);
    HAL_Delay(1000);
    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI|RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.LSIState = RCC_LSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_RTC;
  PeriphClkInit.RTCClockSelection = RCC_RTCCLKSOURCE_LSI;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */